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VIRAL DISEASES part II. Andrews’ p501-525. Molluscum contagiosum. Poxvirus MCV-1 to -4 and variants MCV-2 in HIV Worldwide Children, sexually active adults and immunosuppressed Direct contact. Lesions are smooth surfaced, firm and dome shaped pearly papules
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VIRAL DISEASESpart II Andrews’ p501-525
Molluscum contagiosum • Poxvirus • MCV-1 to -4 and variants • MCV-2 in HIV • Worldwide • Children, sexually active adults and immunosuppressed • Direct contact
Lesions are smooth surfaced, firm and dome shaped pearly papules • A central umbilication is characteristic • Clinical pattern depends on the group affected • When restricted to only the genital area in a child the possibility of sexual abuse must be considered • Secondary infections may occur
Seen in 10-30 % of AIDS pts • Helper T-cell count of less than 100 • Giant lesion may be confused with BCC • Henderson-Patterson bodies – basophilic inclusion bodies
treatment • Topical tretinoin or imiquimod • Extraction • Light cryotherapy • Cantharadin • Curettage • podophyllotoxin
Human monkeypox • Rare • More than 90% of cases occur in children under 15 • Fatality rate of 11% • Disease is clinically similar to smallpox • Fever followed by vesiculopustular eruption • Develop following contact with wildlife sources
Picornavirus group • RNA • Only coxsackieviruses, the echoviruses, and enterovirus type 71 are significant causes of skin disease
Enterovirus infections • Person to person transmission occurs by the intestinal-oral route and less commonly the oral route • Usually the diagnosis is by clinical characteristics
herpangina • Disease of children worldwide • Coxsackievirus and echovirus • Acute onset of fever, ha, sore throat, dysphagia, anorexia, and sometimes a stiff neck • Yellowish white, vesicles in the throat, surrounded by an intense areola • Most frequently on the anterior faucial pillars, tonsils, uvula, or soft palate
Lesions coalesce and ulcerate leaving a shallow crater • Lesions disappear in 5-10 days • Treatment is supportive • Topical anesthetics or allopurinol mouthwash
Hand-Foot-and-Mouth Disease • Infection begins with a fever and sore mouth • 90% have oral involvement • Lesions are small rapidly ulcerating vesicles surrounded by a red areola • Buccal mucosa, tongue, soft palate, and gingiva • Lesions on hands and feet • Red papules that quickly turn to gray vesicles • With a red halo
Typically lasts less than a week • Treatment is again supportive • Topical anesthetics • Coxsackievirus A-16 • Distribution and presence of skin lesions differentiates this from herpangina
Boston Exanthem Disease • Occurred as an epidemic in Boston • Caused by echovirus 16 • Consisted of sparsely scattered pale red macules and papules • Chiefly on the face chest and back • Now an uncommon cause of viral exanthems
Eruptive pseudoangiomatosis • Young children during or immediately following a viral illness develop red papules that resemble angiomas • Face trunk and extremities • Resolve spontaneously within 10 days • Echoviruses 25 and 32 have been implicated
PARAMYXOVIRUS GROUP • RNA viruses • Measles • Rubella
Measles(rubeola, morbilli) • Worldwide disease • Commonly affects children under age of 15 months • Respiratory spread with an incubation of 9-12 days • Immunizations are highly effective • Prodrome- fever, malaise, conjunctivitis and prominent upper respiratory symptoms
A macular or maculopapular eruption appears after 1-7 days • Anterior scalp line and behind the ears • Quickly spreads over the face and involves the entire body by day 3 • Purpura may be present • Koplik’s spots are pathognomonic, appear during the prodrome
Pink macules with minimally elevated papules with confluence
Koplik’s Spots • cluster of tiny bluish white papules with an erythematous areola on buccal mucosa opposite premolar teeth
complications • OM • Pneumonia • Encephalitis • Thrombocytopenic purpura • Infection in pregnant patients is associated with fetal death
DX • Clinical- high fever, Koplik’s spots, conjunctivitis, upper respiratory symptoms, rash • course and prognosis • maximum intensity of rash reached in 3 days • rash fades 5-10 days • self limited • death 1 in 3000 • chronic complication, subacute sclerosing panencephalitis
RUBEOLAmanagement • Acute • Vitamin A • decreases morbidity and mortality • given to severe measles even if no nutritional deficit is suspected • vaccine • MMR given at 12-15 months, and 4-6 years
Rubella • German measles, 3-day measles • benign contagious viral disease • etiology • Togavirus • transmission • inhalation of aerosolized respiratory droplets • incubation • 12-23 days • Vaccination gives lifelong immunity
RUBELLAclinical manifestations • Prodrome- 1-5 days • mild symptoms of malaise, headache, sore throat, eye pain, and moderate temperature elevation • Pain on lateral and upward eye movement is characteristic • precedes eruption by a few hours to a day • children are usually asymptomatic
RUBELLAclinical manifestations • Eruptive phase • begins on neck or face • spreads to trunk and extremities in hours • lesions are pinpoint to 1 cm, round or oval, pinkish or rosy red, macules or maculopapules (purplish lesions of measles and fine punctate yellow-red lesions of scarlet fever) • discrete, grouped or coalesced • arthritis of phalangeal joints may be seen in women
RUBELLA • Diagnosis • Clinical, posterior cervical, suboccipital, and postauricular lymphadenitis occurs in more than half • can be confirmed with serology • course and prognosis • typically mild, requiring only symptomatic treatment • lesions last 24 -48 hours, followed by desquamation • prevention • MMR given at 12-15 months, and 4-6 years
RUBELLA • Forchheimer Spots • red palatal lesions start with onset of rash
Congenital Rubella Syndrome • Infants born to mothers who have had rubella during the first trimester of pregnancy • transplacental transmission as high as 80% in the first trimester • Typical anomalies include IUGR, deafness, mental retardation, cataracts, retinopathy, cardiac defects, and “blueberry muffin” rash. • Prior to pregnancy antibody titer should be verified. Immunization is contraindicated in pregnancy.
Asymmetric Periflexural Exanthem of Childhood (APEC) • AKA unilateral laterothoracic exanthem • Children 8 mo to 10 yrs • Cause is unknown • Viral origin has been proposed • Symptoms of mild upper respiratory or gastrointestinal infection usually precede the eruption
Erythematous macules and papules involving the axilla, lateral trunk and flank. In this patient the exanthem progressed to bilateral distribution but maintained left-sided predominance
Erythematous papules coalesce to form poorly marginated morbilliform plaques • Mild pruritis • Lesions begin unilaterally, close to a flexural area, usually the axilla • Centrifugal spread to adjacent trunk and extremity • The contralateral side is involved in 70% of cases, asymmetrical nature is maintained
Lymphadenopathy is seen in 70% • Last 2-6 weeks on average • Resolves spontaneously • Topical steroids or oral antibiotic are of no benefit • Oral antihistamines
Erythema Infectiosum(Fifth Disease) • Worldwide benign infectious exanthem • Parvovirus B19 • Spread by respiratory droplets • Viral shedding has stopped by the time the exanthem has appeared • Incubation 4-14 days • prodrome • pruritus, low-grade fever, sore throat, malaise seen in 10% of cases
Three distinct overlapping stages • facial erythema. Red papules on the cheeks that rapidly coalesce. Resembles erysipelas. “slapped cheek.” • net pattern erythema. Fishnet like pattern, begins on extremities then extends to trunk • recurrent phase. Eruption may reappear following emotional upset or sunlight exposure over next 2-3 weeks.
Lacy, reticulated skin eruption over the arm during the second stage of the exanthem